Detecção com técnicas moleculares de Leifsonia xyli subsp. xyli e Xanthomonas albilineans em cana-deaçúcar.

• Autor(a) principal: Dias , Vanessa Duarte
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000007gb9
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6824
• topic: Fitobactérias; Infecções latentes; LAMP; Nested-PCR; Saccharum sp.; Latent infections; LAMP; Nested-PCR; Saccharum sp.; Phytobacteria; AGRONOMIA::FITOSSANIDADE

The sugarcane production areas are increasing in Brazil due to increased ethanol consumption by flex fuel cars. The planted area is growing, but productivity has been declining in recent years, and factors such as incidence of diseases in the crop may be contributing to this situation. Among the diseases, bacteria such as scald of the leaves and ratoon stunting disease are of great importance to the crop because they can reduce productivity by up to 30%. In addiction and the symptoms are not always displayed in the field, thus requiring advanced techniques to detect such bacterial diseases For Leifsonia xyli subsp. xyli, which causes rickets in the ratoon cane sugar control measure most commonly used besides varietal resistance is thermally treating the billets that will serve seedlings. Thus, the purpose of the first study was to perform the heat water treatment of billets with the addition of kasugamycin antibiotic dosage 300mL/100L H2O in order to try to reduce bacterial escape from the standard treatments, as also in other time and temperature combinations proposed: T1 = 52°C/30 '; T2 = 52°C/1hr; T3 = 50°C/1hr; T4 = 50°C/2hrs; T5 = 52°C/30 '+ antibiotic; T6 = 52°C/1hr + antibiotic; T7 = 50°C/1hr + antibiotic; T8 = 50°C/2hrs + antibiotic; T9 = antibiotic and T10 = control. Moreover, among techniques for diagnosis of such diseases, the most used by laboratories are the serological tests which have the advantage of quantitatively detecting the presence of bacteria on the stems but, however, has the disadvantage of detecting only when the bacterial population is relatively high. PCR technique that is one of the techniques considered most sensitive, has not been used in practice, as this high sensitivity has not been used, the protocols do not detect bacterial diseases in the case of latent infection, where bacterial title is relatively low. So the other work aimed at improving the Xanthomonas albilineans detection developing a LAMP protocol, and compared to other techniques of detection and isolation in semiselective medium, PCR and nested PCR for both symptomatic samples and for asymptomatic and the latter where population in general pathogen is low, we improved Nested one protocol to detect the leaf scald in latent infections by comparing the vascular fluid extraction techniques combined with four different DNA extraction protocols.